Automatic musical instrument.



A. SWENSEN. AUTOMATIC MUSICAL INSTRUMENT. u'vucmou FILED IUNE28. 191s.

Patented July .3, 1917.

1,231,809 2 SHEETS-SHEETI s9 MW A. SWENSEN.

AUTOMATlC MUS1CAL INSTRUMENT APPLICATlOH HLCD JUNE 28. I916. I 1,231,809.

Patented July 3, 1917.

2 SHEETS-SHEET 2.

UNITED STATES PATENT OFFICE.

ALFRED SWENSEN, 0F CICERO, ILLINOIS, ASSIGNOR TO THE CABLE COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

AUTOMATIC MUSICAL INSTRUMENT.

Specification of Letters Patent.

Patented July 3, 1917.

To all whom it may concern:

Be it known that I, ALFRED SWENSEN, a citizen of the United States, residing at Cicero, in the county of Cook and State of Illinois, have invented new and useful Improvements in Automatic Musical Instruments, of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawing, formin a part of this specification.

My invention relates to automatic musical instruments, and more specifically to a device for varying the degree of air tension produced by an air pump.

Among the objects of my invention is to rovide a device of this character which shall be simple in construction, efiicient in operation and easy of adjustment.

In the drawings, in which one embodiment of my invention is shown- Figure 1 is a front elevation of a player piano, the upper front panel being broken away to show the roll box and the lower front panel being broken away to show the air pump and expression device;

Fig. 2 is a section through the expression device on the line 2-2 of Fig. 1;

Fig. 3 is a section through the expression device on the line 3-3 of Fig. 2;

Fig. 4 is a longitudinal vertical section of the manual valve which controls the expres sion device; and

Fig. 5 is a section on the line 55 of Fig. 4.

Referring now to the drawings in detail, the player piano shown comprises a casing 10, roll box 11 located in the upper part of the casing, a motor driven air pump 12 for exhausting the air from the action wind chest, and motor, conduits 13 and 14 leading from the wind chest to the air pump, an expression device 15 for varying the degree of air tension produced in the wind chest by the air pump, and a conduit 16 leading from the expression device to the conduit 13.

The air pump operates ,to exhaust the air from the wind chest through the conduits 13 and 14 and'the expression device operates to modify the air tension produced by the air pump by admitting atmospheric air more or less freely through the conduit 16 to the con-luit 13. The expression device 15 may be controlled automatically from the note sheet 16' or manuallv by means of the valve mechanism 17.

The expression device itself comprises a series of chambers 18, 19, 20, 21 and 22, separated by partitions 23, 24, 25 and 26, each two adjacent chambers being in communication with each other through two ports 27 and 28, 29 and 30, 31 and 32, 33 and 34, respectively. The chamber 18 is in communication with the atmosphere through the port 35 and the chamber 22 is in communication with the conduit 16 through the port 36. The flow through the ports 27, 29, 31, 33 and 35 is controlled by means of yielding adjustable pressure actuated valve mechanisms 37, 38, 39, 40 and 41, respectively, and the flow through the ports 28, 30, 32 and 35 is controlled by positively actuated valve mechanisms 42, 43, 44, and 45, respectively, these latter valve mechanisms being controlled both automatically, from the note sheet, and manually, from the valve 17. The upper part of the expression device is provided with a plurality of staggered transversely extending barriers 46 forming a muffler.

' The valve mechanisms 37 38, '39, 40 and 41 are all alike, each comprising a valve proper 47, a bent spring lever 48 fulcrumed on a screw 48' and having one end connected to the valve proper, an adjusting stem or rod 49 having a threaded connection with the other end of the spring lever 48, and a dash pot bellows 5O acting on the valve proper 47 to prevent flutterin and vibration of the valve. The threade end of the rod 49 extends through an opening in the lever 48 and is threaded into a U-shaped nut 51 which straddles the lever to prevent the nut from rotating with the stem. The dash pot bellows 50 is provided with a restricted opening 52 through which the air is forced as the bellows expands and collapses and is mounted on a supporting bridge 53 which straddles the stem 49 and is secured to the partition beneath. A U-shaped spring 54 tends to hold the dash pot bellows expanded. The stem 49 extends out through the wall of the expression box and is provided with a button 55 for turning it.

The valve mechanisms 42, 43, 44 and 45 are allalike and each comprises .a valve proper 56 and a diaphragm pneumatic 57 to which the valve 56 is secured. The pneumatics 57 of the valve mechanisms 42, 43, 44 and 45 are connected with ports in the tracker through the conduits 58, 59, 60 and (31, respectively, leading to the junction block 62 and through the conduits (33, (34, (35 and 66, respectively, leading from the junction block to the tracker (37. Each pneumatic 57 is provided with a bleed (58 to per mit the pneumatic to collapse when the note sheet closes the corresponding tracker aperture. The junction block is provided with a plurality of ports (39, 70, 71 and 72 leading to the conduits 58, 59, G0 and (31, respectively, which ports are controlled by a manually operated slide valve 73 having an opening 74 movable selectively into registration with any one of the ports 69, 70, 71 and 72. The slide "alve is held in place and guided by means of a guide rod 75 engaging a groove 76 in the slide valve.

In operation the air pump 12 is driven to exhaust air from the wind chest through the conduits 13 and 14 and the expression device 15 is operated to modify the air tension produced by the air pump by admitting air more or less freely through the conduit 16 to the conduit 13 either automatically, by means of perforations in the note sheet 16, or manually, by means of the slide valve 73. By means of the note sheet any one or any combination of the valves 4:2, 43, 4st and d5, may be closed. If all of the valves are open the flow of air through the expression box is practically unimpeded except by the yielding valve 37. If the valve 42 alone is closed the flow of air is impeded by the yielding valve-37 and also by the yielding valve 38. If the valve 43 alone is closed the How of air is impeded by the yielding valve 37 and also by the yielding valve 39. In short the closing of any one or any combination of the valves -12, 4:3, 44 and 45 puts in commission the corresponding one or combination of the ielding valves 38, 39, 40 and -11 to impede the flow of air. These yielding valves can be set by means of the buttons to give any desired degree of resistance to the flow of air. By adjusting the buttons so that each of the yielding valves will afford a different degree of resistance and by using various combinations of the yielding valves the total resistance afforded to the flow of air through the expression box may be varied either gradually or suddenly over a wide range. This variable resistance to the flow of air through the expression box of course results in a cor]esponding variation of the air tension produced in the conduit 14 and wind chest, the tension in the wind chest increasing with the increased resistance in the expression box and decreasing as the resistance decreases.

Having thus described my invention what I claim as new and desire to secure by Letters Patent is 1. An automatic musical instrument comprising an exhaust air pump, and means for varying the degree of air tension produced by said pump comprising two chambers, one of said chambers being in communication with the atmosphere and the other with said air pump, two ports each affording communication between said chambers, a yielding valve for one of said ports actuated by the air pressure on said valve, and a positively acting valve for the other port.

2. A sheet controlled automatic musical instrmnent comprising an exhaust air pump, and means for varying the degree of air tension produced by said pump comprising two chambers, one of said chambers being in communication with the atmosphere and the other with said air pump, two ports each affording communicaton between said chambers, a yielding valve for one of said ports actuated by the air pressure on said valve, and a sheet controlled positively acting valve for the other port.

3. An automatic musical instrument comprising an exhaust air pump, and means for varying the degree of air tension produced by said pump comprising two chambers, one of said chambers being in communication with the atmosphere and the other with said air pump, partitions separating said chambers having two ports each affording communication between said chambers, a yielding valve for one of said ports actuated by the air pressure on said valve, and a positively acting valve for the other port.

An automatic musical instrument comprising an exhaust air pump, and means for varying the degree of air tension produced by said pump comprising a series of charm hers, the first of said series being in communication with the atmosphere and the last of said series being in communication with the air pump, two ports between each two adjacent chambers each affording communication therebetween, a yielding valve for one of said ports actuated by the air pressure in said valve, and a positively acting valve for the other port.

5. An automatic musical instrument comprising an exhaust air pump, and means for varying the degree of air tension produced by said pump comprising two chambers, one of said chambers being in communication with the atmosphere and the other with said air pump, two ports each affording communication between said chambers, a yielding valve for one of said ports actuated by the air pressure on said valve, a valve for the other port and means for positively actuating said last valve to close its port.

6. An automatic musical instrument comprising an exhaust air pump, and means for varying the degree of air tension produced by said pump comprising two chambers, one of said chambers being in communication with the atmosphere and the other with said air pump, two ports each aflording communication between said chambers,

a yielding valve for one of said ports actuated by the air pressure on said valve, a valve for the other port and means for positively actuating said last valve to close its port comprising a pneumatic.

7. An automatic musical instrument comprising an exhaust air pump, and means for varying the degree of air tension produced by said pump comprising a series of chambers, the first of said series being in communication with the atmosphere and the last of said series being in communication with the air pump two ports between each two adjacent chambers each affording communication therebetween, a yielding valve for one of said ports actuated by the air pressure on said valve, a valve for the other port, and a pneumatic for actuating said valve.

8. An expression device for varyin the degree of air tension produced by an ex aust air pump comprising a series of chambers, the first of said series being in communication with the atmosphere and the last of said series having means for aiit'ording communication with the air pump, two ports between each two adjacent chambers, each port affording communication therebetween, a yielding valve for one of said ports actuated by the air pressure on said valve, and a positively acting valve for the other port.

9. An expression device comprising two chambers, an atmospheric air inlet in communication with one of said chambers, an exhaust outlet in communication with the other of said chambers, and partitions separating said chambers having two ports each port in communication between said chambers, a yielding valve for one of said ports actuated by the air pressure on said valve, a valve for the other port and means for positively actuating said last valve to close its port.

10. An expression device comprising two chambers, an atmospheric port leading to one of said chambers, a yielding valve for said atmospheric port actuated by the air pressure on said valve, an exhaust passage leading from the other chamber, two ports each affording communication between said chambers, a yieldin valve for one of said ports actuated by t e air pressure on said valve, a valve for the other port, and means for positively actuating said valve to close its port.

11. An expression box comprising a series of chambers, an atmospheric port leading to the first chamber of said series, a yielding valve for said atmospheric port actuated by the air pressure on said valve, an exhaust passage leading from the last of said chambers, two ports between each two adjacent chambers, each affording communication therebetween, a yielding valve for one of said ports actuated by the air pressure on said valve, a valve for the other port, and means for positively actuating said last valve to close its port.

12. An expression device for varying the degree of air tension produced by an exhaust air pump comprising a series of chambers, the first of said series being in communication with the atmosphere and the last of said series having means for aifording communication with the air pump, a port between each two adjacent chambers, a yielding valve for each port actuated by the air pressure on said valve for restricting the flow of air through said port, and selective movable means for rendering said valves inactive to restrict the flow of air between said chambers.

13. An expression device for varying the' In witness whereof, I have hereunto subscribed my name.

ALFRED SWENSEN.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. G. 

